State Chart

State charts for modeling control logic

A state chart is a representation of an event-driven (reactive) system. In an event-driven system, the system makes a transition from one state or mode to another, if the condition defining the change is true.

For example, you can use a state chart to represent the automatic transmission of a car. The transmission has these operating states: park, reverse, neutral, drive, and low. As the driver shifts from one position to another, the system transitions from one state to another, such as from park to reverse.